Method of molding decorative elements for consumer packaging

ABSTRACT

A method of molding a decorative product packaging, comprising the steps of: molding a product container or cap; applying a UV curable liquid to surfaces and/or cavities in the container or cap; then exposing the UV curable liquid to UV radiation to form a solid coating adhered to surfaces and/or filling cavities on the container or cap. Gate marks, gate wells, frosting, cutter marks, and cuts and abrasions in the packaging surface are no longer visible after the UV curable coating has cured.

RELATED APPLICATIONS

This is a continuation of U.S. patent application Ser. No. 10/285,189filed 31 Oct. 2002.

FIELD OF THE INVENTION

The present invention relates to manufacturing methods used to provideconsumer packaging, particularly, cosmetic cases, with attractivecolored coatings and molded colored elements.

BACKGROUND OF THE INVENTION

The cosmetic industry serves a range of markets, from young teenagers toolder, more mature customers. In the more upscale markets it isdesirable for the cosmetic packaging to project elegance andsophistication, particularly where the product is priced at a relativelyhigh price point. In a more youthful market, marketers are prefer ayounger, fresher, or funky look.

It would be desirable to provide a method and process for providing anew decorative element suitable for consumer packaging that iseyecatching, and which gives the appearance of high cost and quality,yet which can be fabricated very economically.

SUMMARY OF THE INVENTION

A method of molding a decorative product packaging, comprising the stepsof: molding a transparent or semi-transparent or opaque productcontainer or cap; applying a UV curable liquid to surfaces and/orcavities in the container or cap; then exposing the UV curable liquid toUV radiation to form a solid coating adhered to surfaces and/or fillingcavities on the container or cap. The present invention providesdramatic effects where the container or cap are clear or tinted, andessentially transparent, because the solid coating can be clear orcolored, and provides a striking contrast to the container or cap.However, the invention is effective and useful also where the containeror cap are opaque, instead or clear or tinted.

Other objects, aspects and features of the present invention in additionto those mentioned above will be pointed out in or will be understoodfrom the following detailed description provided in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A-1C shows a side elevation view of an embodiment of a cosmeticcontainer cap made in accordance with the methods of the presentinvention showing a series of steps of using the UV curable liquid in acavity.

FIG. 2A-2C is a side elevation view of an embodiment of a cosmeticcontainer made in accordance with the methods of the present inventionshowing a series of steps of using the UV curable liquid applied to acontainer surface.

DETAILED DESCRIPTION OF THE DRAWINGS

The present invention is applicable to clear, tinted or opaquesubstrates, and is particularly suited for clear and tinted cosmeticcontainers and caps that will benefit from a dramatic surface coating orfilled cavity in a contrasting color. However, the invention as claimedherein is not limited to specific applications, and the term substrateshould be understood to broadly encompass not only molded products, butvirtually any product of any materials, including materials which areclear, tinted or opaque, and which can be selected from plastic, rubber,metal, stone, glass, wood, ceramic, and composites thereof.

Generally, the invention comprises the steps of: forming a substratehaving a plurality of surfaces and/or a cavity therein; applying to oneor more of said surfaces, or filling said cavity, with a UV curableliquid; and exposing said UV curable liquid to a UV light source of asufficient intensity and for a sufficient time to cure said UV curableliquid to a solid mass contained in said cavity.

The UV curable liquid is can be selected from a number of different UVcurable polymer systems. A UV curable polymer system typically comprises1-3% of a photoinitiators; 15-60% of reactive diluents, 25%-90% of anoligomer polymer; and 1-50% of additives and fillers. Polymers used inUV curable polymer systems can include polyurethanes, epoxies,polyesters and acrylates. Specific commonly used monomers for thepolymer include N-vinylpyrrolidone, hydroxyethylacrylate,(poly)ethyleneglycol diacrylate, trimethylolpropanetriacrylate,norbornylacrylate, and styrene. Another suitable polymer system is thethiol-ene polymer system (also known as mercaptoesters). Commerciallyavailable UV curable polymer systems include products from Master Bond,Inc., Hackensack, N.J., Tangent Industries, Winsted, Conn.; DaicelChemical Industries, Ltd., Sakai Osaka Japan, and Ctech LLC, NewHartford, Conn. A suitable thiol-ene polymer system is available fromCtech, LLC. The preferred UV curable liquid is a product that when curedwill have good optical qualities, as this is typically indicative of thefinish and look desired in the process of the invention. These productsare typically cured at ambient temperatures, or at temperatures at orbelow 100° C. using a UV light source. Typical cure times range from 5seconds to 5 minutes depending upon the wave length and intensity of theUV light and the thickness being cured. The preferred UV curable liquidis an acrylate formulation. One commercially available formulation thatcould be us invention is the Ctech 8166-4A formulation, which can becured to a tack free surface with 5 minutes UV exposure at 100° C. Apreferred UV light source is a UV lamp providing a UV intensity of isabout 115 mW/cm2 at 365 nm. The UV light source desirably provides abroad range of wavelengths from 250-500 nm, which will cure materialsmuch faster than if only the 365 nm radiation were delivered.

The UV curable liquids can be tinted to a specific color to provide avisually striking color depth, or additives and fillers can be used toprovide a metallic or pearly appearance. Also glitter or flake fillerscan be added to give a glitter appearance. Dense metallic fillers can beused to increase the mass of the package.

Where UV curable liquid is to be used as a coating it is applied one ormore surfaces of the substrate using a precision dispensing system. Adip process may also be used for a coating of UV curable liquid. Thesurface should be clean and dry, but otherwise no particular surfacepreparation or pretreatment is required. It has been found that themethod of the invention results in a coating in which gate marks, gatewells, frosting, cutter marks, and cuts and abrasions in the substratesurface virtually disappear, even though the coating is transparent orsemi-transparent. The material can be applied as a uniform coating onthe substrate to provide a smooth finish, or only to selected parts ofthe substrate to provide an embossed effect.

Where UV curable liquid is to be used as a plug in a cavity it isprovided in the cavity using a precision dispensing system to providethe correct amount of liquid. Again, the cavity is preferably clean anddry, but no particular surface pretreatment is required. The cavityshapes may be selected from all types of designs, including ornamentaldesigns, and lettering (such as a product brand), and logos. The cavitymay be formed by molding the substrate or by cutting or other mechanicalmeans.

The UV curable liquid can be applied directly to a substrate in a freeform, pattern or design, and cured, providing a product with an embossedsurface texture where the liquid is applied.

The UV curable liquid can be used to increase the shape of thickness ofthe substrate as well as acting as a decorative coating. In some cases,the UV curable liquid can be used for functional purposes, such as tostrengthen the substrate or to act as a mechanical lock between twocomponents.

In another embodiment, the UV curable liquid can be poured in multiplelayers to provide a desired effect of appearance. For example, there maybe multiple layers of differently tinted liquids poured. Or a firstlayer may be poured, and then decorative elements such as glitter,confetti type plastic dots or shapes, or decals, surface decoration,medallions/logos, or name plates may be placed on the first layer, andanother layer poured, to provide the effect of decorative elementsembedded between two or more layers of the UV curable liquid. Thisprocess can be extended to include three, four or more layers, withdecorative elements placed between some or all of such layers. In suchcases, the multiple layers and decorative elements can be applied to thesubstrate then a final UV curing step can take place, or the UV curingstep can take place after each layer of UV curable liquid is applied tothe substrate.

Referring now to FIG. 1A, a cosmetic container cap 10 is shown having acavity 12. FIG. 1B shows the delivery of a UV curable liquid 14 in acavity 12 by a precision dispensing system 16. FIG. 1C shows a step ofcuring the UV curable liquid 14 by exposure to a UV lamp 18 to cure andset the UV curable liquid 14.

Referring now to FIG. 2A a cosmetic container cap 30 is shown having asurface 32. FIG. 2B shows the delivery of a UV curable liquid 34 tosurface 32 by a precision dispensing system 36. FIG. 2C shows a step ofcuring the UV curable liquid 34 by exposure to a UV lamp 38 to cure andset the UV curable liquid 34.

The finished product made using the processes of the invention has avery attractive appearance that is well suited for both an elegantcosmetic product application and a more youth oriented product.

It is to be appreciated that the foregoing is illustrative and notlimiting of the invention, and that various changes and modifications tothe preferred embodiments described above will be apparent to thoseskilled in the art. Such changes and modifications can be made withoutdeparting from the spirit and scope of the present invention, and it istherefore intended that such changes and modifications be covered by thefollowing claims.

1. A method of diminishing visibility of visible imperfections in thesurface of a transparent or semi-transparent non-film product packaging,comprising the steps of: forming a transparent or semi-transparentnon-film product packaging having a plurality of surfaces, said surfaceshaving one or more of gate marks, gate wells, frosting, cutter marks,cuts and abrasions therein; applying a UV curable liquid to one or moreof said gate marks, gate wells, frosting, cutter marks, cuts andabrasions; exposing said UV curable liquid to a UV light source of asufficient intensity and for a sufficient time to cure said UV curableliquid to a transparent or semi-transparent solid coating adhered tosaid one or more of said plurality of surfaces to diminish visibility ofone or more of gate marks, gate wells, frosting, cutter marks, cuts andabrasions, in said product packaging.
 2. The method of claim 1, whereinsaid UV curable liquid is untinted such that after exposing said UVcurable liquid to a UV light source, said cured solid mass istransparent.
 3. The method of claim 1, wherein said UV curable liquid istinted such that after exposing said UV curable liquid to a UV lightsource, said cured solid mass is tinted.
 4. The method of claim 1,wherein said UV curable liquid contains one or more of additives,fillers, glitter fillers, flake fillers, and decorative elements.
 5. Themethod of claim 1 wherein said product packaging comprises a cosmeticcase.
 6. A method of diminishing visibility of visible imperfections inthe surface of a transparent or semi-transparent non-film productpackaging, comprising the steps of: forming a transparent orsemi-transparent non-film product packaging having a plurality ofsurfaces and a cavity therein, said surfaces and cavity having one ormore of gate marks, gate wells, frosting, cutter marks, cuts andabrasions therein; applying a UV curable liquid to one or more of saidgate marks, gate wells, frosting, cutter marks, cuts and abrasions;exposing said UV curable liquid to a UV light source of a sufficientintensity and for a sufficient time to cure said UV curable liquid to atransparent or semi-transparent solid coating adhered to said one ormore of said plurality of surfaces to diminish visibility of one or moreof gate marks, gate wells, frosting, cutter marks, cuts and abrasions,in said product packaging.
 7. The method of claim 6 where said UVcurable liquid is placed in said cavity.
 8. The method of claim 7,wherein said cavity is shaped as one or more of an ornamental design,lettering, and a logo.
 9. The method of claim 7, wherein said UV curableliquid contains one or more of additives, fillers, glitter fillers,flake fillers, and decorative elements.
 10. The method of claim 7further comprising filling said cavity with multiple layers of UVcurable liquid.
 11. The method of claim 10, further comprising placingdecorative elements between said layers of UV curable liquid.
 12. Themethod of claim 7, wherein said UV curable liquid is untinted such thatafter exposing said UV curable liquid to a UV light source, said curedsolid mass is transparent.
 13. The method of claim 7, wherein said UVcurable liquid is tinted such that after exposing said UV curable liquidto a UV light source, said cured solid mass is tinted.
 14. The method ofclaim 6 wherein said product packaging comprises a cosmetic case. 15.The method of claim 1, wherein said UV curable liquid is applied to saidsubstrate in a free form, pattern or design to provide said substratewith an embossed surface texture.
 16. The method of claim 6, whereinsaid UV curable liquid is applied to said substrate in a free form,pattern or design to provide said substrate with an embossed surfacetexture.